Double Square-spot

Xestia triangulum · Order: Lepidoptera · Family: Noctuidae

Also called: Square-spotted Clay

No source yet on danger. We have no source yet on whether it bites, stings or damages anything.
Double Square-spot
Photo: Donald Hobern, CC BY

The Double Square-spot moth has a wingspan of about 36 to 46 mm. Its forewings are pale brown with two distinctive black marks and a rufous-tinged grey-brown colour, while the hindwings are dark brown.

Source: Wikipedia

How to recognize it

The forewings are pale brown with two black spots and a small basal blotch, a pre-apical costal spot, and a dark cell; hindwings are fuscous.

Source: Wikipedia

Size

Wingspan ranges from 36 to 46 mm (1.4 to 1.8 in).

Source: Wikipedia

Where it lives

Found mainly on forest edges, shrub-covered slopes, heaths, gardens and parkland.

Source: Wikipedia

Life cycle

The species overwinters in the larval stage.

Source: Wikipedia

Where it comes from

Distributed across most of Europe, except Mediterranean islands and the far north of Fennoscandia. Its eastern range extends across the Palearctic to Siberia and south-east to the Black Sea and Iran.

Source: Wikipedia

Lookalikes

It closely resembles Xestia ditrapezium, which has a slightly narrower (or longer) forewing.

Source: Wikipedia

Questions people ask

How can I tell the Double Square-spot apart from similar moths?

Look for the two black marks on the pale brown forewings and the darker cell area; Xestia ditrapezium usually has a narrower forewing.

Source: Wikipedia

When are Double Square-spot moths active?

They fly at night during June and July in the British Isles.

Source: Wikipedia

Same family (Noctuidae)

Ipsilon Dart MothIpsilon Dart MothAgrotis ipsilonDamages trees, gardens or cropsFall Armyworm MothFall Armyworm MothSpodoptera frugiperdaDamages trees, gardens or cropsArmy Cutworm MothArmy Cutworm MothEuxoa auxiliarisDamages trees, gardens or cropsLarge Yellow UnderwingLarge Yellow UnderwingNoctua pronubaDamages trees, gardens or cropsSilver ΥSilver ΥAutographa gammaAmerican DaggerAmerican DaggerAcronicta americanaCan irritate skin

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Double_square-spot

Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia

Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.

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